CVE-2026-65905: tomcat vulnerability

CVE-2026-65905: critical vulnerability affecting tomcat. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2026-65905CVSS 9.8Windows

CVE-2026-65905: tomcat vulnerability

CVE-2026-65905: critical vulnerability affecting tomcat. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
9.8 CRITICAL
EPSS
53.64%
Known exploited
not in KEV
Product
tomcat

What is known

Authentication Bypass by Capture-replay vulnerability in Apache Tomcat's DIGEST authenticator. If, before windowSize requests have been made, a client makes a DIGEST authenticated request with a nonceCount on the upper boundary of the replay window then that request is replayable once only while the associated nonceCount remains within the replay window.   This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.24, from 10.1.0-M1 through 10.1.57, from 9.0.0.M1 through 9.0.120. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.30 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.25, 10.1.58 or 9.0.121, which fix the issue.

Business impact

Successful exploitation of CVE-2026-65905, a critical vulnerability (CVSS 9.8) affecting tomcat, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether tomcat is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

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